A uniform 1.5 T magnetic field points north. If an electron moves perpendicular (90 degrees) with a speed of 2.5x10 ^7 m/s, through this field, what force (magnitude and direction) will act on it?

If the speed of a particle triples ,by what factor does its kinetic energy increase?

Ahot-air balloonist, rising vertically with a constant speed of 5.00 m/s releases a sandbag at the instant the balloon is 40.0 m above the ground. after it is released, the sandbag encounters no appreciable air drag. compute the velocity of the sandbag at 0.250 s after its release.

Do you agree with scientist’s prediction about the warming of alaska and other polar regions?